Key Fossils

Key Fossils

D3444

Site: Dmanisi, Republic of Georgia

Discovered by: A team led by David Lordkipanidze

Age: About 1.77 million years old

Species: Homo erectus

Old timer

This elderly male belonged to a population of Homo erectus that spread from Africa to the Caucasus Mountains in western Asia. Most of his teeth fell out long before he died, and his jaw deteriorated as a result. Members of his social group must have taken care of him. This is some of the earliest known evidence for this kind of group care and compassion in the human fossil record.

This 1.7 million-year-old femur (thigh bone) of a Homo erectus female shows how scientists can sometimes determine an individual’s cause of death, even after fossilization. An abnormal outer layer of bone on her thigh shows evidence of bleeding just before death. After consulting doctors and accounts of wilderness explorers, researchers concluded that an overdose of vitamin A—perhaps from eating a carnivore’s liver, which concentrates vitamin A—caused the bleeding and her death.

KNM-WT-15000

Nickname: Turkana Boy

Site: Nariokotome, West Turkana, Kenya

Date of discovery: 1984

Discovered by: Kamoya Kimeu

Age: About 1.6 million years ago

Species: Homo erectus

The strapping youth

The ‘Turkana Boy’ skeleton has allowed scientists to find out a lot of information about body size, body shape, and growth rates of Homo erectus. Using bilateral symmetry to fill in missing bone (e.g., the missing left upper arm bone can be reconstructed as the mirror image of the right upper arm bone), his skeleton is over 90% complete.

The size and shape of the pelvis shows he was male, and his teeth tell he was eight or nine years old. He was 1.6 m (5 ft 3 in) tall and weighed 48 kg (106 lb) when he died; if he had reached adulthood, he might have grown to nearly 1.85 m (6 ft). Turkana Boy’s cranial capacity at death was 880 cubic centimeters, but scientists estimate it would have reached 909 cubic centimeters if he had grown into adulthood. There is evidence that he was growing up at a rate similar to modern humans, and he may have undergone an adolescent growth spurt characteristic of modern teenage boys. His cause of death at such a young age is unknown.

His long and slender body is evidence of an early human adaptation to the hot, dry climate of Africa. His long legs and narrow pelvis helped him walk farther, increasing his home range, and maybe even run long distances.

Trinil 2

Nickname: Java Man

Site: Trinil, Java, Indonesia

Date of discovery: 1891

Discovered by: Eugene Dubois

Age: Between 1 million and 700,000 years old

Species: Homo erectus

Indonesia's "Java Man"

While searching for fossils in Java, physician Eugène Dubois uncovered the tophalf of an early human skull in 1891. This skull, Trinil 2, is long, with a flat forehead and distinct browridges and a sagittal keel, though many of its features have been worn flat with age. Dubois named a new species, Pithecanthropus erectus after this specimen in 1894, but Ernst Mayr reassigned Trinil 2 to Homo erectus in the 1950s.